Skip to main content
U.S. flag

An official website of the United States government

Sub-sampling genetic data to estimate black bear population size: A case study

January 1, 2007

Costs for genetic analysis of hair samples collected for individual identification of bears average approximately US$50 [2004] per sample. This can easily exceed budgetary allowances for large-scale studies or studies of high-density bear populations. We used 2 genetic datasets from 2 areas in the southeastern United States to explore how reducing costs of analysis by sub-sampling affected precision and accuracy of resulting population estimates. We used several sub-sampling scenarios to create subsets of the full datasets and compared summary statistics, population estimates, and precision of estimates generated from these subsets to estimates generated from the complete datasets. Our results suggested that bias and precision of estimates improved as the proportion of total samples used increased, and heterogeneity models (e.g., Mh[Chao]) were more robust to reduced sample sizes than other models (e.g., behavior models). We recommend that only high-quality samples (>5 hair follicles) be used when budgets are constrained, and efforts should be made to maximize capture and recapture rates in the field.

Citation Information

Publication Year 2007
Title Sub-sampling genetic data to estimate black bear population size: A case study
DOI 10.2192/1537-6176(2007)18[179:SGDTEB]2.0.CO;2
Authors C.A. Tredick, M.R. Vaughan, D.F. Stauffer, S.L. Simek, T. Eason
Publication Type Article
Publication Subtype Journal Article
Series Title Ursus
Series Number
Index ID 70030212
Record Source USGS Publications Warehouse
USGS Organization